[rbak-nsp] BGP Flapping after update with malformed ASPATH

[Николай Михайлов]

Hello,

The fix is available on 12.1.1.12p15 version of the software.

Thanks.

2018-05-30 11:08 GMT+02:00 Marcin Kuczera <marcin at leon.pl>:

> On 2018-05-29 14:19, Marcin Kuczera wrote:
>
> On 2018-05-29 13:07, Wojciech Wrona wrote:
>
> Marcin Can You tell anything more? I didn't notice any problem in decoded
> aspath in update message (my post before) what did i wrong ? :)
>
> AS Path was in fact empty, all ASes in {} brackets were taken from
> confederation, but AS-Path itself was empty, and that should not be sent
> from RouteServer.
>
> An update - after deeper analysing, according to RFC - update was correct,
> and SEOS should accept it but:
> - this is a very interesting case of misconfiguration that should not
> happen in normal usage cases
> - can only happen in IX when connected to RS that removes it's AS as first
> AS from AS-patch
> - it looks like RFC bug, because such config was never considered as
> possible and maybe RFC needs to be updated in future to avoid such cases.
>
> Regards,
> Marcin
>
>
>
>
> Marcin
>
>
> Best regards,
>
> --
> Wojciech Wrona
>
> W dniu 29.05.2018 o 12:41, Marcin Kuczera pisze:
>
>
> Fixed.
> The problem was located in TPIX, and had been fixed.
> And that was not a SEOS fault. SEOS behaves correctly. Question is why
> Juniper passed malformed update...
>
> Regards,
> Marcin
>
> On 2018-05-29 10:58, Wojciech Wrona wrote:
>
> Hi everyone,
> It looks like we've managed to find another strange problem with BGP on
> SEOS. In the night one of our peers session started to flap with following
> message:
> May 29 10:52:01: [0001]: %BGP-6-INFO: 195.149.233.1 UP
> May 29 10:52:15: [0001]: %BGP-6-INFO: 195.149.233.1 DOWN - Notification
> sent
> May 29 10:52:15: [0001]: %BGP-6-INFO: 195.149.233.1 send NOTIFICATION:
> 3/11 (update: malformed ASPATH) with 21 byte data. mxReadMs=1555
>
> It does not look like previously mentioned attribute flag error. Does
> anyone had something simillar ? It is a session with route server, so i
> know about "no enforce first-as" option and it is turned on, it was working
> fine till this night with no configuration change on our side.
>
> "show bgp malform update" looks like this:
> May 29 10:52:15 Malformed UPDATE msg (nbr 195.149.233.1, context
> 0x40080001, 77 bytes, repeated 5 times, reason: Invalid msg) -
>  ffff ffff ffff ffff ffff ffff ffff ffff 004d 0200 0000 3240 0101 0040
> 0212 0104 0000 17d9 0000 183e 0000 1840 0000 1967 4003 04c3 95e9 6480 0404
> 0000 0000 c007 0800 0073 5fc3 95ef ff16 c395 ec
>
> SEOS version SEOS-12.1.1.11p7-Release
>
> Thanks in advance,
> Best regards,
>
>
> --
>
> Marcin Kuczera / Wiceprezes Zarządu / CTO
> +48 32 440 80 71/ marcin.kuczera at leon.pl
>
> Leon Sp. z o.o.
> ul. Kilińskiego 33d, 44-200 Rybnik
> http://www.leon.pl/
>
> INTERNET | TELEWIZJA | TELEFON
>
> KRS 0000223101 Sąd Rejonowy w Gliwicach
> Kapitał zakładowy 576.700 zł
> NIP: 6332068698
>
>
> _______________________________________________
> redback-nsp mailing listredback-nsp at puck.nether.nethttps://puck.nether.net/mailman/listinfo/redback-nsp
>
>
>
>
> _______________________________________________
> redback-nsp mailing listredback-nsp at puck.nether.nethttps://puck.nether.net/mailman/listinfo/redback-nsp
>
>
> --
>
> Marcin Kuczera / Wiceprezes Zarządu / CTO
> +48 32 440 80 71/ marcin.kuczera at leon.pl
>
> Leon Sp. z o.o.
> ul. Kilińskiego 33d, 44-200 Rybnik
> http://www.leon.pl/
>
> INTERNET | TELEWIZJA | TELEFON
>
> KRS 0000223101 Sąd Rejonowy w Gliwicach
> Kapitał zakładowy 576.700 zł
> NIP: 6332068698
>
>
> _______________________________________________
> redback-nsp mailing listredback-nsp at puck.nether.nethttps://puck.nether.net/mailman/listinfo/redback-nsp
>
>
> --
>
> Marcin Kuczera / Wiceprezes Zarządu / CTO
> +48 32 440 80 71/ marcin.kuczera at leon.pl
>
> Leon Sp. z o.o.
> ul. Kilińskiego 33d, 44-200 Rybnik
> http://www.leon.pl/
>
> INTERNET | TELEWIZJA | TELEFON
>
> KRS 0000223101 Sąd Rejonowy w Gliwicach
> Kapitał zakładowy 576.700 zł
> NIP: 6332068698
>
> _______________________________________________
> redback-nsp mailing list
> redback-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/redback-nsp
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/redback-nsp/attachments/20180621/1e295448/attachment.html>